INTRODUCTION. 47 



ill a latent state until tlie young animal has attained a 

 definite age corresponding often with that in which it 

 first appeared in the parent. For the prevention of out- 

 breaks of special disorders various means are adopted. 



Inoculation depends for its value upon the fact that 

 some diseases do not occur twice in the same subject^ and 

 when artificially induced have a mild character. 



Vaccination consists in securing immunity from a 

 severe disorder by bringing on an attack of a closely 

 allied but very mild disease. 



Special Breeding consists in the crossing of animals of 

 a breed predisposed to a disorder with animals of a breed 

 manifesting no such tendency, as in crossing shorthorns 

 with less carefully bred animals. 



Special legislative measures, with which we shall after- 

 wards have to deal, are necessary to check contagious 

 disorders. 



The treatment of inflammation is complicated in accord- 

 ance with the complex conditions of that pathological 

 state, and the effects of these processes. We ujust 

 remember that inflammation is in very many cases salutary 

 and that it must therefore be encouraged under the 

 following circumstances ; when reparative, constructive, or 

 usefully destructive. Reparative inflammation is the 

 means by which injuries are repaired, and when a con- 

 siderable amount of new tissue has to be produced, as in 

 filling up an abscess cavity, constructive inflammation 

 causes granulative repair. In the removal of foreign bodies, 

 whether introduced from without or resulting, from death 

 of a part, as in sloughing, inflammation is usefully des- 

 tructive. Inflammation under these circumstances must 

 be carefully watched, and either promoted or controlled 

 as occasion may require. If the process becomes sluggish, 

 as in indolent ulcers, on account of deficiency either of 

 local or constitutional energy, stimulants must be applied 

 or administered ; while if the local changes are intensely 

 acute and give rise to a high state of fever sedative 

 means must be adopted locally, and general sedatives 

 and antiphlogistics be used. At the same time the 



